This invention relates to a modular printer. The invention relates particularly, but not necessarily exclusively, to a modular commercial printer for effecting high speed, digital, photographic quality, commercial printing. The invention relates specifically to a print head assembly for a modular commercial printer.
In high speed printing, large printing presses are daisy-chained together to print predetermined pages of publications which are then secured together to form the publications. Such printing presses occupy an extremely large volume and are very expensive.
The applicant has also proposed a commercial printer using a number of floor mounted printers having pagewidth print heads. This commercial printer is intended for extremely high production rates such as up to five 180 page documents per second.
To achieve such high production rates, large quantities of consumables need to be readily available for the printers. Thus, once again, such a commercial printer needs to occupy an extremely large volume although the cost of such a printer is considerably lower than equivalent high end, commercial printers which do not use the applicant""s Memjet (Memjet is a trade mark of Silverbrook Research Pty Ltd) technology.
The applicant has recognised a need for a commercial printer which occupies a smaller volume and which has a lower throughput rate but of the same quality as the applicant""s previously proposed Memjet commercial printer.
According to the invention, there is provided a print head assembly for a printer, the print head assembly including at least one print head molding which supports an elongate print head for effecting pagewidth printing, said at least one molding defining at least one ink gallery for supplying ink to the chip, at least that portion of the molding carrying the chip being arcuate when viewed end-on to define a receiving zone; and
a feed means arranged adjacent said at least one molding so that a portion of said feed means nests in the receiving zone such that the print head chip lies within the footprint of the feed means.
Preferably, the assembly includes two moldings, each of which supports a print head, each molding having the same arcuate shape when viewed end-on and one of the moldings nesting within the other, at least the print head chip of said one molding being within the footprint of the feed means.
Further, each molding preferably defines a plurality of galleries for supplying different inks to its associated print head. In this specification the term xe2x80x9cinkxe2x80x9d is to be understood in a broad sense as including visible inks of various colors, an ink which is invisible in the visible spectrum but is visible in the infrared spectrum, a fixative for fixing the ink on the print media and a varnish for coating printed matter on the print media.
Each molding may include an air channel for feeding filtered air to the print chip for inhibiting the build up of debris and foreign matter on the print chip.
The assembly may include a control means for controlling operation of the, or each print head chip, said control means being mounted on said at least one molding and communicating with said print head chip via a connector. The connector may be a flex PCB wrapped about a part of a periphery of said at least one molding. In the case where two moldings are provided, each molding may have a flex PCB associated therewith wrapped about a part of its periphery.
Preferably, the flex PCB is wrapped about a convex part of a periphery of each molding.
The feed means may be a roller having a radius of curvature corresponding to a radius of curvature of said portion of said at least one molding to nestle snugly in said receiving zone. Accordingly, by xe2x80x9cfootprintxe2x80x9d is meant the projection of that part of the roller between two tangents drawn on opposed sides of the roller normal to a diametral plane of the roller.
It will be appreciated that, by having each molding substantially scythe shaped, when view end-on, the print head chips of the moldings are brought into close proximity to a rotational axis of the feed means thereby enabling a closely controlled print media to print head gap to be maintained.
The invention extends also to a print engine for a printer, the print engine including
a first print head assembly, as described above; and
a second print head assembly, as described above, arranged in opposed, aligned relationship with the first print head assembly.